diff mbox

still nfs problems [Was: Linux 2.6.37-rc8]

Message ID 1294505384.4181.14.camel@heimdal.trondhjem.org (mailing list archive)
State Not Applicable
Headers show

Commit Message

Trond Myklebust Jan. 8, 2011, 4:49 p.m. UTC
None
diff mbox

Patch

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 996dd89..ad9e5e0 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -33,7 +33,6 @@ 
 #include <linux/namei.h>
 #include <linux/mount.h>
 #include <linux/sched.h>
-#include <linux/vmalloc.h>
 #include <linux/kmemleak.h>
 
 #include "delegation.h"
@@ -459,25 +458,27 @@  out:
 /* Perform conversion from xdr to cache array */
 static
 int nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *entry,
-				void *xdr_page, struct page *page, unsigned int buflen)
+				struct page **xdr_pages, struct page *page, unsigned int buflen)
 {
 	struct xdr_stream stream;
-	struct xdr_buf buf;
-	__be32 *ptr = xdr_page;
+	struct xdr_buf buf = {
+		.pages = xdr_pages,
+		.page_len = buflen,
+		.buflen = buflen,
+		.len = buflen,
+	};
 	struct nfs_cache_array *array;
 	unsigned int count = 0;
+	struct page *scratch;
 	int status;
 
-	buf.head->iov_base = xdr_page;
-	buf.head->iov_len = buflen;
-	buf.tail->iov_len = 0;
-	buf.page_base = 0;
-	buf.page_len = 0;
-	buf.buflen = buf.head->iov_len;
-	buf.len = buf.head->iov_len;
-
-	xdr_init_decode(&stream, &buf, ptr);
+	scratch = alloc_page(GFP_KERNEL);
+	if (scratch == NULL)
+		return -ENOMEM;
 
+	xdr_init_decode(&stream, &buf, NULL);
+	xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
+	xdr_enter_page(&stream, buflen);
 
 	do {
 		status = xdr_decode(desc, entry, &stream);
@@ -506,6 +507,8 @@  int nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *en
 		} else
 			status = PTR_ERR(array);
 	}
+
+	put_page(scratch);
 	return status;
 }
 
@@ -521,7 +524,6 @@  static
 void nfs_readdir_free_large_page(void *ptr, struct page **pages,
 		unsigned int npages)
 {
-	vm_unmap_ram(ptr, npages);
 	nfs_readdir_free_pagearray(pages, npages);
 }
 
@@ -530,9 +532,8 @@  void nfs_readdir_free_large_page(void *ptr, struct page **pages,
  * to nfs_readdir_free_large_page
  */
 static
-void *nfs_readdir_large_page(struct page **pages, unsigned int npages)
+int nfs_readdir_large_page(struct page **pages, unsigned int npages)
 {
-	void *ptr;
 	unsigned int i;
 
 	for (i = 0; i < npages; i++) {
@@ -541,13 +542,11 @@  void *nfs_readdir_large_page(struct page **pages, unsigned int npages)
 			goto out_freepages;
 		pages[i] = page;
 	}
+	return 0;
 
-	ptr = vm_map_ram(pages, npages, 0, PAGE_KERNEL);
-	if (!IS_ERR_OR_NULL(ptr))
-		return ptr;
 out_freepages:
 	nfs_readdir_free_pagearray(pages, i);
-	return NULL;
+	return -ENOMEM;
 }
 
 static
@@ -577,8 +576,8 @@  int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page,
 	memset(array, 0, sizeof(struct nfs_cache_array));
 	array->eof_index = -1;
 
-	pages_ptr = nfs_readdir_large_page(pages, array_size);
-	if (!pages_ptr)
+	status = nfs_readdir_large_page(pages, array_size);
+	if (status < 0)
 		goto out_release_array;
 	do {
 		unsigned int pglen;
@@ -587,7 +586,7 @@  int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page,
 		if (status < 0)
 			break;
 		pglen = status;
-		status = nfs_readdir_page_filler(desc, &entry, pages_ptr, page, pglen);
+		status = nfs_readdir_page_filler(desc, &entry, pages, page, pglen);
 		if (status < 0) {
 			if (status == -ENOSPC)
 				status = 0;
diff --git a/fs/nfs/nfs2xdr.c b/fs/nfs/nfs2xdr.c
index 5914a19..b382a1b 100644
--- a/fs/nfs/nfs2xdr.c
+++ b/fs/nfs/nfs2xdr.c
@@ -487,12 +487,6 @@  nfs_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry, struct nfs_se
 
 	entry->d_type = DT_UNKNOWN;
 
-	p = xdr_inline_peek(xdr, 8);
-	if (p != NULL)
-		entry->eof = !p[0] && p[1];
-	else
-		entry->eof = 0;
-
 	return p;
 
 out_overflow:
diff --git a/fs/nfs/nfs3xdr.c b/fs/nfs/nfs3xdr.c
index f6cc60f..ba91236 100644
--- a/fs/nfs/nfs3xdr.c
+++ b/fs/nfs/nfs3xdr.c
@@ -647,12 +647,6 @@  nfs3_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry, struct nfs_s
 			memset((u8*)(entry->fh), 0, sizeof(*entry->fh));
 	}
 
-	p = xdr_inline_peek(xdr, 8);
-	if (p != NULL)
-		entry->eof = !p[0] && p[1];
-	else
-		entry->eof = 0;
-
 	return p;
 
 out_overflow:
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 9f1826b..0662a98 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -6215,12 +6215,6 @@  __be32 *nfs4_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry,
 	if (verify_attr_len(xdr, p, len) < 0)
 		goto out_overflow;
 
-	p = xdr_inline_peek(xdr, 8);
-	if (p != NULL)
-		entry->eof = !p[0] && p[1];
-	else
-		entry->eof = 0;
-
 	return p;
 
 out_overflow:
diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index 498ab93..7783c68 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -201,6 +201,8 @@  struct xdr_stream {
 
 	__be32 *end;		/* end of available buffer space */
 	struct kvec *iov;	/* pointer to the current kvec */
+	struct kvec scratch;	/* Scratch buffer */
+	struct page **page_ptr;	/* pointer to the current page */
 };
 
 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
@@ -208,7 +210,7 @@  extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
 		unsigned int base, unsigned int len);
 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
-extern __be32 *xdr_inline_peek(struct xdr_stream *xdr, size_t nbytes);
+extern void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen);
 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
 extern void xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index cd9e841..cff0974 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -569,29 +569,112 @@  void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p)
 	xdr->iov = iov;
 	xdr->p = p;
 	xdr->end = (__be32 *)((char *)iov->iov_base + len);
+	xdr->page_ptr = NULL;
+	xdr->scratch.iov_base = NULL;
+	xdr->scratch.iov_len = 0;
 }
 EXPORT_SYMBOL_GPL(xdr_init_decode);
 
 /**
- * xdr_inline_peek - Allow read-ahead in the XDR data stream
+ * xdr_set_scratch_buffer - Attach a scratch buffer for decoding data.
  * @xdr: pointer to xdr_stream struct
- * @nbytes: number of bytes of data to decode
+ * @buf: pointer to an empty buffer
+ * @buflen: size of 'buf'
  *
- * Check if the input buffer is long enough to enable us to decode
- * 'nbytes' more bytes of data starting at the current position.
- * If so return the current pointer without updating the current
- * pointer position.
+ * The scratch buffer is used when decoding from an array of pages.
+ * If an xdr_inline_decode() call spans across page boundaries, then
+ * we copy the data into the scratch buffer in order to allow linear
+ * access.
  */
-__be32 * xdr_inline_peek(struct xdr_stream *xdr, size_t nbytes)
+void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen)
+{
+	xdr->scratch.iov_base = buf;
+	xdr->scratch.iov_len = buflen;
+}
+EXPORT_SYMBOL_GPL(xdr_set_scratch_buffer);
+
+static int xdr_set_page_base(struct xdr_stream *xdr,
+		unsigned int base, unsigned int len)
+{
+	unsigned int pgnr;
+	unsigned int maxlen;
+	unsigned int pgoff;
+	unsigned int pgend;
+	void *kaddr;
+
+	maxlen = xdr->buf->page_len;
+	if (base >= maxlen)
+		return -EINVAL;
+	maxlen -= base;
+
+	if (len > maxlen)
+		len = maxlen;
+
+	base += xdr->buf->page_base;
+
+	pgnr = base >> PAGE_SHIFT;
+	xdr->page_ptr = &xdr->buf->pages[pgnr];
+	kaddr = page_address(*xdr->page_ptr);
+
+	pgoff = base & ~PAGE_MASK;
+	xdr->p = (__be32*)(kaddr + pgoff);
+
+	pgend = pgoff + len;
+	if (pgend > PAGE_SIZE)
+		pgend = PAGE_SIZE;
+	xdr->end = (__be32*)(kaddr + pgend);
+	return 0;
+}
+
+static int xdr_set_next_page(struct xdr_stream *xdr)
+{
+	unsigned int newbase;
+
+	newbase = (1 + xdr->page_ptr - xdr->buf->pages) << PAGE_SHIFT;
+	newbase -= xdr->buf->page_base;
+
+	return xdr_set_page_base(xdr, newbase, PAGE_SIZE);
+}
+
+static __be32 * __xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes)
 {
 	__be32 *p = xdr->p;
 	__be32 *q = p + XDR_QUADLEN(nbytes);
 
 	if (unlikely(q > xdr->end || q < p))
 		return NULL;
+	xdr->p = q;
 	return p;
 }
-EXPORT_SYMBOL_GPL(xdr_inline_peek);
+
+static __be32 *xdr_page_inline_decode(struct xdr_stream *xdr, size_t nbytes)
+{
+	size_t cplen;
+	void *cpdest;
+	__be32 *p;
+
+	if (xdr->p == xdr->end && xdr_set_next_page(xdr) < 0)
+		return NULL;
+
+	p = __xdr_inline_decode(xdr, nbytes);
+	if (p != NULL)
+		return p;
+
+	if (nbytes > xdr->scratch.iov_len)
+		return NULL;
+	cplen = (char *)xdr->end - (char *)xdr->p;
+	cpdest = xdr->scratch.iov_base;
+	memcpy(cpdest, xdr->p, cplen);
+	cpdest += cplen;
+	nbytes -= cplen;
+	if (xdr_set_next_page(xdr) < 0)
+		return NULL;
+	p = __xdr_inline_decode(xdr, nbytes);
+	if (p == NULL)
+		return NULL;
+	memcpy(cpdest, p, nbytes);
+	return xdr->scratch.iov_base;
+}
 
 /**
  * xdr_inline_decode - Retrieve non-page XDR data to decode
@@ -605,13 +688,9 @@  EXPORT_SYMBOL_GPL(xdr_inline_peek);
  */
 __be32 * xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes)
 {
-	__be32 *p = xdr->p;
-	__be32 *q = p + XDR_QUADLEN(nbytes);
-
-	if (unlikely(q > xdr->end || q < p))
-		return NULL;
-	xdr->p = q;
-	return p;
+	if (xdr->page_ptr == NULL)
+		return __xdr_inline_decode(xdr, nbytes);
+	return xdr_page_inline_decode(xdr, nbytes);
 }
 EXPORT_SYMBOL_GPL(xdr_inline_decode);
 
@@ -671,16 +750,12 @@  EXPORT_SYMBOL_GPL(xdr_read_pages);
  */
 void xdr_enter_page(struct xdr_stream *xdr, unsigned int len)
 {
-	char * kaddr = page_address(xdr->buf->pages[0]);
 	xdr_read_pages(xdr, len);
 	/*
 	 * Position current pointer at beginning of tail, and
 	 * set remaining message length.
 	 */
-	if (len > PAGE_CACHE_SIZE - xdr->buf->page_base)
-		len = PAGE_CACHE_SIZE - xdr->buf->page_base;
-	xdr->p = (__be32 *)(kaddr + xdr->buf->page_base);
-	xdr->end = (__be32 *)((char *)xdr->p + len);
+	xdr_set_page_base(xdr, 0, len);
 }
 EXPORT_SYMBOL_GPL(xdr_enter_page);